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direct line; direct communication; connecting directly; through service; nonstop service
この電車は空港まで直通で便利だと評判だよ。
This train goes directly to the airport and is known for being convenient.
直通バスに乗れば乗り換えなしで行けるので楽だ。
It's easy because you can get there without transfers by direct bus.
社長室への直通電話があるのは秘書だけらしい。
It seems only the secretary has a direct line to the company president's office.