 Re: If conditional
It's not a matter of grammatical correctness but of meaning.
The expression "If only" expresses a wish - ie that things could be different from reality. The thing wished for is hypothetical. So the verb must express that - which is done in English by using the second form of the verb. As Lewis suggests in "The English Verb" second form verbs express "distance from here and now reality". This may be distance in time - ie past rather than present, but also distance from reality itself - ie a hypothetical statement.
In this case, the here and now reality is "I don't eat spinach". So the second form verb is necessary to state the hypothetical alternative situation : I wish I liked spinach! If only I ate spinach!
Notice the second part of your sentence is irrelevant. The second form verb is necessary just to express the meaning of the part introduced by "if only!."
in your example, however, the speaker continues by making a hypothetical prediction based on the hypothetical situation. Notice again the use of the second form verb (would rather than will) to indicate that it is hypothetical.
I hope that helps, and would strongly recommend Lewis' book. |