1 I had problems - У меня были проблемы (Past simple,т. к. глагол стоит в прош вр)
I was trying to solve (Past Continuous, есть was и продолжение действие (суффикс -ing ))
2 There were (Past Simple, глагол стоит в прош вр)
Had (Past Simple, глагол стоит в прош вр)
3 was being formed (Past Continuous в пассивном залоге, есть спутник at that moment)
4 had faced (Past Perfect, т к have и focus в 3 форме)
Lost (Past Simple, глагол стоит в прош вр)