# 1เลือกประเภทBy the time we ______ at the airport, the plane ______.arrived / had already taken offarrive / took offhad arrived / takes offwas arriving / had taken off
# 2เลือกประเภทShe ______ her homework before she ______ TV.does / watchedhad done / watcheddid / had watchedwas doing / watches
# 4เลือกประเภทShe ______ nervous because she ______ her presentation before.had been / never gaveis / giveswas / had never givenhad been / had given