English Grammar and Usage

Butter up means to say nice things to someone for personal gain. 

Care for means to look after somebody. 

'Ago' is used to indicate time elapsed before the present moment ('I saw him two months ago'). 'Before' typically requires a reference point or event ('two years before that'), 'since' implies from a past time until now, and 'for' indicates duration. With simple past tense and a time reference from now, 'ago' is correct.

In time clauses introduced by 'when', we use the present simple tense to refer to future time, not the future tense. This is a standard grammar rule in English. 'Will arrived' is grammatically incorrect (double future markers), while 'will be arriving' and 'will have arrived' are future forms that don't belong in time clauses.

The given sentence is in present simple tense, and none other auxiliary, except 'is', confirms to the same tense. 'Known to' is the correct usage. Hence, option 4.

This is a zero conditional sentence expressing a general scientific truth or universal fact. Zero conditionals use present simple in both clauses: 'If you boil water, it turns into vapours'. This describes what always happens under these conditions.

Sentence (A) is incorrect because after 'stop', we need the gerund form ('raining') not the infinitive ('rain'). The verb 'stop' is followed by -ing when meaning to cease an action. Sentence (B) is correct: 'If it stops raining, we can go to the terrace'.

Sentence A is incorrect because 'If I were an umbrella, I would lend it to you' has a pronoun error - 'I' and 'it' don't match. It should be 'I would lend you mine' or 'I would lend it to you' if the subject matched. Sentence B is correct because 'If I had an umbrella, I would lend it to you' properly uses second conditional with consistent pronouns and correct tense structure.

Sentence A is correct because it uses proper first conditional structure with present simple 'If you are looking' and modal 'you may find'. Sentence B is incorrect because it uses 'will' in the if-clause 'If you will look' - 'will' should never appear in the if-clause of a conditional sentence.

Option B is correct because 'have finished' is the present perfect tense form, which properly indicates a completed action. Option A incorrectly uses the present continuous 'are finished' which doesn't convey the meaning of completing an action.

Both sentences are ungrammatical in standard English. The correct idiomatic phrase is 'you had better go there' rather than 'you will better' or 'you should better'. Since neither sentence A nor B is correct, option D is the right choice.

Option B is correct because it uses the simple past 'came' in the if-clause, which is proper for second conditional sentences. Option A incorrectly uses 'would come' - the word 'would' should never appear in the if-clause.

Third conditional for past unreal situations requires 'would have + past participle' in the result clause to match 'had + past participle' in the if-clause. Option B correctly uses 'would have attended', while A incorrectly uses 'would attend' (present form) with a past if-clause.

Sentence B correctly uses 'in case he comes here' which means 'if he happens to come here.' Sentence A incorrectly adds 'if' before 'in case,' creating redundancy. The word 'in case' already functions as a conditional connector, so adding 'if' before it is grammatically incorrect and repetitive.

Sentence A correctly uses 'so long he is here' meaning 'as long as he is here' or 'during the time he is here.' Sentence B incorrectly adds 'in case' before 'so long,' creating confusion. 'So long' already functions as a time conjunction, and adding 'in case' makes the sentence grammatically incorrect and unclear.