Fill in: a/an, the or– . 1 .... experiment can help a researcher prove their theory 2 ............ antibodies exist in our blood. 3 The project gives free medical care to ......... poor. 4 ............ lab is where scientists conduct experiments. 5 ...... knowledge is the foundation on which science was built.
1. - experiment can help a researcher prove their theory
2.An antibodies exist in our blood.
3.The project gives free medical care to the poor.
4.A lab is where scientists conduct experiments
5.A knowledge is the foundation on which science was built.