ought to (ellipsis)

Point 145 in the category of MODALITY and ELLIPSIS is defined as:

‘ought to’ without a following verb where the previous main verb is understood.

There is an important note in the comments section of the EGP:

This is a very low-frequency form in both the learner and native speaker data.

A search for collocates up to 4 spaces to the left of ought to.

1 THEY (PPHS2 ) 210

2 THAN (CSN ) 128

3 THINK (VV0 ) 47
4 REALLY (RR ) 42
5 WAY (NN1 ) 39

*google search does not allow a search for the full stop.  This makes it very hard to find examples of it.