1. be grounds for a feeling or action In the interview he gave some grounds for optimism.
on the grounds of /that
2. be grounded in
Her argument was grounded in fact.
3. good/reasonable/sufficient/valid grounds
have/give grounds for
He rejected the invitation on grounds of poor English.
He turned down the invitation on the grounds that his English was not good enough.
On the grounds of inadequate English , he declined the invitation.
On the grounds of inadequate English writing skill , I deliberately delayed the study of the mode"one paragraphed a week".