A.do not B.will not C.shall not D.not to
A.right，correct and safe B.sufficient，efficient and coefficient C.nice，tidy and in good working condition D.tight，staunch and strong
A.cargo elevators B.conveyor belts C.ramps D.derricks and winches for cargo handling
A.it B.this C.that D.which
A.on B.in C.from D.to
