They may require help in getting in and out of automobiles, trains, airplanes, etc., but travel on the whole is very good for them.
(They; may require; help in getting in and out of automobiles, trains, airplanes, etc.) (travel on the whole; is; very good)
They travel on the whole
may require is
help in getting in and out of automobiles, trains, airplanes, etc.
very good