A particular source of confusion concerns the use of the verb be as a subjunctive, especially in the past tense, in the context of phrases beginning with if. Where something hypothetical is being proposed were is the correct form to use because the mood is subjunctive: If that were to happen, I would be worried.
If, however, a statement of fact or probability is being proposed, then was is the correct form, representing the indicative mood: If he was ill, he seems to have recovered now.
Overuse of the subjunctive mood should be avoided, because it can sound more formal than simpler alternatives. One way to avoid overuse of subjunctives is to insert the word should (lest she should disagree).
Phrasal Verbs Phrasal verbs are constructed through the combination of an existing verb with an adverb or preposition, or both (carry on, come across, do up, leave out, look after, look forward to, run over, try out). The object of the verb usually follows the adverb or preposition (do up the parcel; look after the child). Caution should be exercised in relation to phrasal verbs, since they often have secondary, often figurative, meanings that are not obvious from their superficial appearance. Some uses of phrasal verbs are literal in their meaning (go out after dinner; tie up the dog), while others acquire extended meanings (go out with a girl; tie down with work; tie up all day; visit with oneâ€™s parents). Note that there is some risk involved in extending ordinary verbs in such a way where they are not already well established, because such coinages may be considered nonstandard slang.
Negation In order to turn a statement into the negative the usual method is to insert the word not after the main verb or the first auxiliary verb: We are not millionaires. He was not wearing a suit. They were not being fair.
In cases where the main verb or the auxiliary verb is not be, the correct procedure is to insert the auxiliary verb do before the word not: I do not have the documents you are talking about. We did not go shopping today.
Note, however, that for poetic effect not occasionally follows the main verb: Where she lives now I know not.