1. You are bound to fluctuate at times.
    有时你肯定会摇摆不定的。

2. Such parents fluctuate between saying no and giving in — but neither response seems satisfactory to them.
    这样的父母会在拒绝和让步之间动摇不定 -- 但是好象没有哪种办法能使他们感到满意。