make passive sentences starting with THERE IS...... or THERE ARE using the reporting verb in brackets in the tense given, plus a standard or perfect infinitive of BE as instructed, plus the phrase given
1. many species still undiscovered( think- present simple)- standard
2. considerable support for the idea ( understand- present simple)- standard
3. any need to act immediately( not feel- past simple) - standard
4. enough supplies to go round ( presume- past simple )- standard
5.a shortage of medicines ( report- past simple) perfect
6. several reasons for the failure( say- present simple)- perfect