John is now working as an interpreter because he________an unusual ability to learn languages quickly.
A:performs
B:possesses
C:observes
D:supports
马六甲海峡被称为“海上生命线”是因为它沟通了( )
乘法公式的探究及应用:
某物体以30m/s的初速度竖直上抛,不计空气阻力,g=10m/s2,5s内物体的( )