it's ( )( )( ) Mr Zhang ( )( ) his English 对张先生来说提高英语水平不容易
问题描述：
it's ( )( )( ) Mr Zhang ( )( ) his English 对张先生来说提高英语水平不容易
答
it's ( not)( easy)( for) Mr Zhang ( to )( improve) his English
答
not easy for
to improve