Bothofmybrothersarenowmarried，soIhavetwo_____.
A、sister-ins-law
B、sisters-in-law
C、sisters-in-law
D、sister-in-law
_____he speaks softly is no proof that he is kind.
A、Since
B、As
C、That
D、Because
Copernicus maintained that the earth_____round the sun.
A、moves
B、moved
C、moving
D、move
_____you understand this rule ，you‘ll have no difficulty in dealing with such
problems.
A、While
B、Though
C、Unless
D、Once
_____hespeakssoftlyisnoproofthatheiskind.
A、Since
B、As
C、That
D、Because