You____that letter to James. However ， you didn't.
A、oughttowriteB
「句意」你本应该给詹姆斯写信，然而，你没写。
「难点」oughttohavewritten是虚拟语气，与本句句意相符。
Toobtainasatisfactoryresult，onemustapplytwo（）ofpaintonacleansurface.
Breadandbutter____likedbyWesterners.
Thebackgardenofourhousecontainsalawn，____verypleasanttositoninsummer.
YouthatlettertoJames.However，yodidn't（）.
ProfessorJohnsonissaid_____somesignificantadvanceinhisresearchinthepastyears.
