Question

The mobile phone is useful to us, and we can use it _______others at any place.
A. call                    B. calling                 C. to call

Answer 1

C

试题分析：句意:手机对我们是有用的，我们可以随时随地能够用它。be useful to sb对某人来说是有用的；call sb给某人打电话。at any place在 任何地方。use sth to do用某物做某事。根据句意故选C。