-2

"The only thing holding me back is the available colours."

or

"The only thing holding me back are the available colours."

It seems to me like a glitch either way. I slightly favour the second one though.

2

The rule is simple. The verb agrees with the subject of the sentence.

The only thing...is... [correct]

The only thing...are... [incorrect]

0

You can say 'The only thing is' or 'The only things are', but you can not say 'the only thing are'

Not the answer you're looking for? Browse other questions tagged or ask your own question.