built vs had built
1863
How do the tens­es and as­pects in English cor­re­spond tem­po­ral­ly to one an­oth­er?
105201
" could " vs. " could have "
102159
“Has been” vs. “was”
71690
"Is" vs "has been" in English
80268
Past participle vs being+past participle
128120
"Has been" vs "was"
34460
"Named" vs "called"
118270
Difference between "has + verbed" and "had + verbed"
35695
Past perfect or past simple with before
15478
passing vs having passed
95245
When should I use "didn't" instead of "haven't"?
21041
past simple or past perfect why
77813
Using perfect constructions after "since"
154084
Having done something,... vs Doing something,
85034
"If something was" vs "If something were"
92969
"got" vs. "have got"
65426
Difference between Simple Past and Past Perfect