CLAUSES OF PURPOSE

Clauses of Purpose are introduced with so that / in order that in the following way:

so that

+ will / can(reference to the present) + Infinitive

in order that + would / could(reference to the past) (informal construction)

e.g. We bought more food so that we would have enough for the extra guests.

so that

+ may / might + Infinitive

in order that + shall / should(formal construction)

e.g. The President left early so that he should not be late for his next meeting

in case + present / past tense

e.g. Take an umbrella with you in case it gets cold.

e.g. They set off early in case the traffic was heavy.

Negative purpose can be expressed by:

so that + can't / couldn't / won't / wouldn't + Infinitive

e.g. They've locked the gate so that we can't get in.

e.g. He left an hour ago so that he wouldn't be caught in the traffic.

for fear + might / should

e.g. They asked their neighbours to keep an eye on the house for fear burglars might break in.

Clauses of Purpose follow the rule of the sequence of tenses.

e.g. I'll leave early so that I'll be home before they come.

e.g. He avoided mentioning it so that he wouldn't offend her.

Notes

1. The idea of purpose can also be rendered by gerundial phrases:

for + Gerund à A kettle is used for boiling water

with a view to + Gerundà We gathered here with a view to reaching a decision.

with the aim of + Gerundà He opened an account with the aim of saving money.

2. Negative purpose can also be expressed by:

so as not to + Infinitive (when the subject of the verb is also the subject of the infinitive) à We are staying in this weekend so as not to spend any money.

(NOT:He left early not to miss the train)

for fear of + Gerund à She didn't make a noise for fear of waking her parents.

prevent + noun / pronoun + (from) + Gerund à It's impossible to prevent the cat from scratching the furniture.

avoid + Gerund à You should avoid carrying heavy bags if you have a bad back.