Bythetimeof1969,thereweremanyspaceexplorations.
A: havebeen
B: mustbe
C: hadbeen
D: musthavebeen
A: havebeen
B: mustbe
C: hadbeen
D: musthavebeen
举一反三
- Thelightison.He___________________athome.（） A: musthavebeen B: wouldbe C: mustbe D: willbe
- ThatwasthefirsttimeI()abroad.() A: was B: havebeen C: hadbeen D: be
- Iwouldhavegoneshoppingwithyou,butI_____sotiredthatIwenttobedquiteeraly. A: were B: was C: hadbeen D: havebeen
- Itwasthefirsttime______I______here. A: when;hadcome B: that;havebeen C: when;came D: that;hadbeen
- Tomlookssopaletoday．He____ill.（） A: mustbe B: hadtobe C: shouldbe D: shallbe