1 a I entered Mr Green’s office to1 talk to him b We came in the house to put out the lights c I came back to take care of my parents d She winked at me because to let me know that she was joking e I have come to give you a piece of advice

2 a He looked for someone to share his life with in order not to/so as not to feel so miserable b I didn’t drop in at your home last night in order not to/so as not to disturb you c I won’t light my Havana in order not to/so as not to bother her d He destroyed all proof against him in order not to/so as not to be discovered e I put on the stove in order not to/so as not to be cold

3 a He went to prison for holding up a chemist’s b A flowerpot is for growing plants (in) c These pictures are not for selling d A book is for reading e You’ll be punished for not having done/for not doing your homework

4 a She’s studying to become a very important person in life b I was so happy for having finished my studies c I didn’t open the door in order not to/so as not to see them d A rubber is for removing your pencil marks (with) e We went on with the deal in order not to/so as not to leave them high and dry at the last minute f I would like to take tomorrow off to accompany my husband to the doctor g They went on a hunger strike to get better conditions in gaol h They bought a country pad to have some piece and quiet i I’ve just bought a CD player to give it to my daughter for her birthday j I have bought some clothes-pegs to hang the washing out k He did not tell her what happened in order not to/so as not to worry her l In order to/So as to/To get there before dark, we must leave now/We must leave now (in order/so as) to get there before dark m She was friendly to him to nick his wallet n They mugged him to swipe his walkman o She was taken to the police station for lifting some records from the shop next door p We filled the car up in order not to/so as not to run out of petrol q I put the music louder in order not to/so as not to hear what they were talking about r I didn’t answer the phone in order not to/so as not to talk to him s I shut up in order not to/so as not to interfere in matters which had nothing to do with me t He married her to spend the rest of his life with her u You must take an exam tomorrow to test you on your French v She hid a tiny microphone in his house to spy upon him w I put out the central heating in order not to/so as not to waste fuel x I bought my son an ice-cream wafe for having been a good boy y I’ll buy you the bike I promised for getting/having got full marks in your history paper z She set off for Paris before sunrise to be there by midday

5 a She’s helping him with his project so that2 he can go/he will go/he goes with her on holiday b These brave men and women gave their lives so that/in order that the humankind should/might/would have a better world c I’ll give you some money so that you can pay/you will pay/you pay for the bus d He did not send her any letter, phone her or write to her so that she would not/could not know he was alive e We are leaving early in the morning so that we will arrive/we shall arrive/we arrive there by noon/We are leaving early in the morning to arrive there by noon

6 a He went to live abroad to avoid paying maintenance to his wife for his four children b He did all his homework to prevent his teacher (from) telling him off/...homework to avoid being told off by his teacher c He disguised as a woman to avoid being recognised/...woman to prevent anybody (from) recognising him d He hid behind a bush to avoid being seen by his pursuers/...bush to prevent his pursuers (from) seen him e He did not report the incident to his superiors to prevent them (from) thinking that he was to blame for it

7 a I’ll leave him a message in the answering machine in case he comes/should come home this afternoon b He did not kiss her lest she (should) reject3 him/...her in case she rejected/should reject him c I did not tell my parents that I had failed my literature paper lest they (should) punish me by making me stay at home in the evenings for a fortnight/...paper in case they punished/should punish me by making... d She didn’t invite him to the opera in case he turned/he should turn down her invitation/...opera lest he (should) turn down her invitation e He went to the same place they met for the first time in case she was there/in case she should be there.

8 a We put the lights off so that nobody would/could/should know that we were in/...off to prevent anybody (from) knowing that we were in b The bank has employed some security guards in order not to/so as not to be held up again/...guards to avoid being held up again/ ...guards to prevent anybody (from) holding them up again/...guards so that they won’t be/can’t be/may not be/aren’t held up again c They didn’t make out an invoice so that we wouldn’t have to pay VAT/They did not make out an invoice so that we should not have to pay VAT/...invoice to prevent us (from) paying VAT d She left her purse at home lest somebody (should) steal it/...home in case somebody stole/should steal it e She put on some music to4 make him know that she was at home f I hailed a cab in order not to/so as not to be late/...cab to avoid being late g I’ve phoned them to have my flat furnished h He kept still for almost an hour lest the enemy (should) see him/...hour in case the enemy saw/should see him i I tore them off a strip so that it would not happen/could not happen again/...to prevent it (from) happening again j I brought the electric drill to hang a picture here k A cassette player is for listening music (with) l He settled the bill at once in order not to/so as not to be surcharged for late payment/...once to avoid being surcharged.../...once to prevent them (from) surcharging him for... m They were taken to the police station for infringing the law n They walled the swimming-pool so that their children would not/could not/should not fall into it and drown/...swimming-pool to prevent their children (from) falling into it and drowning o I’ll give you a photograph of me so that you won’t/don’t forget me/...me to prevent you (from) forgetting me p They took a lot of food with them in order not to/so as not to go hungry/...them to avoid going hungry q She vaccinated her children against smallpox so that they would not/could not/should not catch it/...smallpox to prevent them (from) catching it r I went to live in the country in order not to/so as not to be disturbed/...country so that nobody would/could/should disturb me/...country to avoid being disturbed/...country to prevent anybody (from) disturbing me s She taught her children self-defence so that nobody would/could/should beat them/...self-defence to prevent anybody (from) beating them t I read a lot of German books to improve my German u They shot him dead to make sure that he could not betray them/...dead to prevent him to betray them/...dead so that he could not betray them v He gave them a false name so that nobody would/could/should know his real identity/...name to prevent anybody (from) knowing his real identity w We need a tennis ball to play (with) x He read her one of his poems to impress her y He stood up to them so that they would not/could not/should not bully him/...to them to avoid being bullied/...to them to prevent them (from) bulling him/...to them in order not to/so as not to be bullied z I’ll wait for them in case they (should) come

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1  In order to and so as to may replace to.
2  In order that is possible instead of so that, but it is far less common and very formal.
3  A present or past tense is possible after lest, but the alternatives given in this key are normally preferred: He did not gave her a kiss lest he rejected him.
4  So that is also possible instead of to and in order not to/so as not to if we repeat the subject, but to and in order not to/so as not to sound neater.