SQUINTING MODIFIER: A third problem in modifier placement is described as a "squinting modifier." This is an unfortunate result of an adverb's ability to pop up almost anywhere in a sentence; structurally, the adverb may function fine, but its meaning can be obscure or ambiguous. For instance, in the sentence below, do the students seek advice frequently or can they frequently improve their grades by seeking advice? You can't tell from that sentence because the adverb often is "squinting" (you can't tell which way it's looking). Let's try placing the adverb elsewhere.
Confusion
Students who seek their instructors' advice often can improve their grades.
Repair Work
Student who often seek their instructors' advice can improve their grades.
Repair Work
Students who seek their instructors' advice can often improve their grades.