The police have __________ an investigation into the incident. A: eleased B: launched C: sent D: proceeded

The train was _________ by heavy snow and the passengers had to wait for a few hours. A: eleased B: delayed C: transferred D: educed

Whenthe O2 concentrationislow,asintheperipheraltissues, H+ isboundbyhemoglobinand O2 is_________. A: eleased B: etained C: ound D: split

Everybody in the family has been in low spirits since his father was _____ with cancer. A: eleased B: diagnosed C: undermined D: digested