The adverbial of purpose

§ 104. This adverbial answers the identifying questions what for? for what purpose? It is most frequently expressed by an infinitive, an infinitive phrase or complex.

Jane has come to help us.

I’ve repeated my words for you to remember them.

The meaning of purpose may be emphasized by the composite prepositions in order or so as, which are never used before an infinitive complex.

We must go early in order not to be late.

We hurried so as not to be late.

The adverbial of purpose may also be expressed by a noun, a preposi­tional phrase, nominal or gerundial, introduced by the preposition for.

We reserved this table for lunch.

We use the thermometer for measuring temperature.

After the imperative of the verbs to go and to come another imperative is preferable to the infinitive, as in:

Go and help him. (Not Go to help him.)

Come and wash up. (Not Come to wash up.)

The use is optional for the verb to see.

Come to see me, or Come and see me.

Go to see him, or Go and see him.

The adverbial of result (consequence)

§ 105. The adverbial of result has no identifying questions. It refers to an adjective, a noun with qualitative meaning, or an adverb accompanied by an adverb of degree, such as too, enough, sufficiently, so... (as). The adverbial of result is expressed by an infinitive, an infinitive phrase, or complex.

It is too cold to go out.

The lecturer spoke slowly enough for us to take down everything he said.

He was fool enough to believe it.

John was so fortunate as to get the first prize.

He felt he was enough of a citizen of the world not to mind it.

The adverbial of degree too signals a negative result, enough suggests the necessary amount of quality to perform the action. The correlative phrase so... as implies a realized action, unlike the phrase so as before adverbials of purpose suggesting a hypothetical event. Compare these sentences:

John was so fortunate as to get the first prize (and he got it) - result.

John trained hours so as to get the first prize for boating (we do not know whether he has got it or not) –

purpose.