Language/Lingala/Grammar/Past-progressive-tense
The past progressive form is used to describe things that were done in the past or that happen a lot.
This is the tense that you’ll want to use if you want to say something like ‘I was cooking’ or ‘We were giving’.
It is formed through the combination of the past tense of kozala and the infinitive you want to use.
So for kolamba (to cook), again start with kosala, only this time make the complete version of the past tense, which will be:
nazalaki – I was
ozalaki – you were
azalaki – he/she was
tozalaki – we were
bozolaki – you were (plural)
bazolaki – they were
ezolaki – it was
Next, simply add the infinitive form of the verb. So for kolamba, the past progressive is:
nazalaki kolamba – I was cooking ozalaki kolamba – you were cooking azalaki kolamba – he/she was cooking tozalaki kolamba – we were cooking bozolaki kolamba – you were cooking (plural) bazolaki kolamba – they were cooking ezolaki kolamba – it was cooking
And for kopesa (to give), the past progressive is: nazalaki kopesa – I was giving ozalaki kopesa – you were giving azalaki kopesa – he/she was giving tozalaki kopesa – we were giving bozolaki kopesa – you were giving (plural) bazolaki kopesa – they were giving ezolaki kopesa – it was giving
Source
https://lobalingala.files.wordpress.com/2014/07/23042014-loba-lingala.pdf