汉译英
1._______that Jack has returned.
2._________is a basic assumption of social scientists.
选做：His ability has never been in doubt,but the question is________
1.It is evident
【解析】该题考点为主语从句后置，句首it充当形式主语
2.That nearly all behavior is learned behavior
【解析】该题考察主语从句的用法。主语从句需有连接词that引导，且不能省略
选做：whether he is prepared to work hard
【解析】该题考察表语从句的使用，前文中表示never in doubt,即为肯定之意，而后文中用but转折，表示与前文不一样的感情色彩，即有些怀疑，所以应用表示不确定的引导词whether或if;由于if不能用在表语从句中，故只有使用whether.