【用should,oughtto,或haveto填空：1、He_____(come)at4o'clockiftheplanearrivesontime.2、Ididn'tgoshoppingthismorningasI_____(do)thehomework.3、She_____(come)toseemeyesterday,butsheforgot.4、You_____(ask)forpermissionbefo】

　　用should,oughtto,或haveto填空：

　　1、He_____(come)at4o'clockiftheplanearrivesontime.

　　2、Ididn'tgoshoppingthismorningasI_____(do)thehomework.

　　3、She_____(come)toseemeyesterday,butsheforgot.

　　4、You_____(ask)forpermissionbeforeyouleftthetable.

　　5、Astheydidn'tunderstand,I_____(explain)everyingagain.