choose?

[nado92]

When he retired in 2001, he continued ( do – doing – does-to do) research.

Thanks in advance

 

[The French]

When he retired in 2001, he continued ( do – doing – does-to do) research.

Thanks in advance

Hi Nado,

Is it homework? Maybe you can tell us first your choice and after the teacher can correct you, but try by yourself (It's just a suggestion).

Bye,

 

[nado92]

Hi Nado,

Is it homework? Maybe you can tell us first your choice and after the teacher can correct you, but try by yourself (It's just a suggestion).

Bye,

Hi The French,
No, it isn't.But I saw it 'to do' and doing'

I will choose continue to do.
Waiting your kind reply French.

 

[The French]

Hi The French,
No, it isn't.But I saw it 'to do' and doing'

Hello,

like you I choice to do it seems to me natural, but nonetheless I am not a teacher.

Have a nice day.;-)

 

[bhaisahab]

Hi The French,
No, it isn't.But I saw it 'to do' and doing'

I will choose continue to do.
Waiting your kind reply French.

Yes, "to do" is good, "doing" would be ok as well in this case.