26. What is the difference in usage for like versus as?
Like may be used as a preposition but the general rule is as comes before a clause. If the word is followed by a clause (a group of words with both a subject and a verb), use as: He liked the restaurant, as any gourmet would. If no verb follows, choose like: He walks like a platypus. As and as if are followed by a verb, but like never is. In casual usage, like is gaining steady popularity as a preposition, as in "He tells it like it is" / "She eats ice cream like it is going out of style," which means that the "rule" that like is not followed by a verb can be suspended. You can say, "She felt like meditating." The informal use of like to introduce a clause is fine in conversation or casual writing, but to be grammatically proper, use the "as comes before a clause" rule.
27. What is the rule for determining whether or not to write out a number as a word?
In general, write out the first nine cardinal (1-9) numbers; use figures for 10 and above. Write out the first nine cardinal (1-9) numbers (except for address numbers 2-9, dates, decimals, game scores, highways, latitude/longitude, mathematical expressions, measurement/weight, money/financial data, percentages, proportion, scientific expressions, statistics, technical expressions, temperature, time, unit modifiers, votes, and numbers not written out in a proper noun) and any number that begins a sentence; use figures for 10 and above. The first nine ordinal (1st-9th) numbers are usually written out, especially when describing order in time or location.
28. Does a comma go after i.e. or e.g.?
Both abbreviations i.e. and e.g. are preceded by a mark of punctuation, usually a comma. In American English, both are generally followed by a comma, though not in British English, and are not italicized. E.g. may also be followed by a colon, depending on the construction. In British English, the term is often written as eg with the periods omitted.
29. When do you use that and which?
In current usage, that refers to persons or things and which is used chiefly for things. The standard rule says that one uses that only to introduce a restrictive or defining relative clause - one that identifies the person or thing being talked about. An example is "The fort that Keir built has to be taken down" and the clause "that Keir built" describes which fort has to be taken down, i.e. it is restrictive. In contrast, which is used only with nonrestrictive or nondefining clauses. This type of clause gives additional information about something that has already been identified in the context. An example is "The students have been complaining about the assigned novel, which is hard to understand." The clause "which is hard to understand" is nonrestrictive as it does not indicate the specific novel being complained about. In a sentence including a nonrestrictive clause, the sentence would still be clear even if the clause were omitted. One will find that which sounds more natural than that in such a sentence, which is a great double-check of the grammar. Some people very strictly use that only in restrictive clauses and which in nonrestrictive clauses. However, even in good prose one will find the use of which in restrictive clauses is very common and considered grammatically acceptable. An example is "I would like to find a website which will tell me all about writing a research paper."
30. What is the rule for determining whether to use a or an?
The rule is: Use an before a word beginning with a vowel sound, however the word is spelled. Hence you say an MBA, an hour, but a BA, a horologist. You say either an historical event or a historical event, according to whether you pronounce the h. The rule is that if the h- is sounded, then a is the proper form. The indefinite article a is used before words beginning with a consonant sound, y and w sounds. The sound, not the actual letter, determines which you use. It is not unusual to find a before a word starting with a vowel or an before a word starting with a consonant.
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