题干
—The book is very good, but I don't have money (钱).
—You can ______ your mother ______ some money.
A：thank; for
B：ask; for
C：call; at
D：help; with
答案(点此获取答案解析）
B
角的力
拉物块时，物块做匀速直线运动；当改用与水平方向成
角的力
推物块时，物块仍做匀速直线运动.若
