An occluded front is usually caused by a （).

He usually goes to beijing by （).A.an airB.airC.the airD. airing

The passage suggests that.A．accidents are usually caused by psychological factorsB．acciden

Couriers can usually deliver an item faster than it would have taken if sent___ .A、by

:An error can be caused by attempting to divide by0．A．InterruptB．DefaultC．UndertowD．Ov

Fires resulting from spontaneous combustion are usually caused by the improper disposal of

The making of West Sumatra dish rendangA．is usually done by women.B．represents an old Indi