1 . A terrible earthquake hit the Pacific Ocean ______ the afternoon of March 11, 2020.

A．with

B．of

C．on

D．by

2 . If you drive from the airport, go on the motorway and follow the ______.

A．signs

B．ways

C．points

D．designs

3 . It is difficult to command a new skill, but once ________, it will benefit you for the rest of your life.

A．obtaining

B．obtained

C．to obtain

D．is obtained