Managing mental health in TCM

[yslamac]

The mistake has been indicated below. I don't know why "to" should be deleted in the below sentence. Could someone please explain? Thank you!

Managing mental health in TCM involves ensuring that these two organs to stay in good condition by nourishing the heart and soothing the liver.

Source: HKEAA AS Use of English Past paper (2008)

 

[Rover_KE]

Re: grammar mistakes

Always tell us the source and author of any text you quote, and note that I have changed your thread title.

 

[Tdol]

There's no real explanation, just habit- we ensure that something happens, not to happen.

 

[teechar]

Some verbs can be followed by a full infinitive (to-infinitive), some by a bare infinitive (no to), and some by either. The verb "ensure" happens to belong in the second category.