An antecedent is a word for which a pronoun stands. The pronoun must agree with its antecedent in number. Rule: A singular pronoun must replace a singular noun; a plural pronoun must replace a plural noun. Here are nine pronoun-antecedent agreement rules.
Best Answer: Wrong answer. Well trough is right. But peak is totally wrong. The crest is the highest point on a wave, while the trough, or valley between two waves ...
There are some important terms related to wave like frequency, wavelength, wave number, velocity of wave etc. Two most important parts of waves are crest and trough by which it is travelled from one part to other part. The upper part is called the crest while the lower part is called trough.