Submitted by admin on Sun, 05/03/2015 - 20:18
definition:
Not having or needing a crew or staff:
sentence:
Baxter's book was fiction, but we're seeing the same trade-off now in NASA's decision to cancel further unmanned missions and bring down the Hubble space telescope in order to spend more money on manned spaceflight development.
difficulty:
medium
toefl frequency:
2
toefl classification: