Third, high tariff and threatened by the challenge from the terrestrial system;

三是通话费用高，各地价格差别大，且受到地面系统的有力挑战；

youdao

Third, high tariff and threatened by the challenge from the terrestrial system;

三是通话费用高，各地价格差别大，且受到地面系统的有力挑战；

youdao