1
century before of a century
2
decade before of a decade
3
The day before today
4
month before of a month
5
Year before of a year
6
week before of a week
7
at an earlier time
8
The auxiliar of past simple in negative
9
the plural form of the past tense of be
10
what just happened
11
a done before of present
12
used with used a measurement of time
13
The auxiliar of past simple
14
past tense first- and third-person singular of be
15
For the verbs can be in past
