【C3】A．rarelyB．normallyC．sometimesD．always

A smoky exhaust shows that the engine is （).A.running slowlyB.running normallyC.over－load

【C9】A．rarelyB．fullyC．abundantlyD．fairly

【C11】A．alwaysB．oftenC．sometimesD．never

【C3】A．neverB．frequentlyC．sometimesD．long

【C7】A．rarelyB．essentiallyC．obviouslyD．particularly

【C5】A．mostlyB．partiallyC．sometimesD．rarely