Many languages have idiomatic expressions that do not always make sense to outsiders.

Explain in simple English what the following idiomatic expressions mean. Assume that you are explaining them to nonnative speakers of English.
a. Have an axe to grind
b. Under wraps
c. Come out of left field
d. Hell on wheels
e. Drop the ball
f. Get your act together
g. Stay the course
h. In the limelight
i. Low on the totem pole