This one word will become identical with the sentence, therefore, presenting the same meaning because of the wordy sentence. The best manner to master this idea is to examine their meanings via placing them in a specific sentence or visualizing them through an exciting story. One phrase substitution questions regularly occur in many aggressive tests including SBI PO, United States, CAPF, CDS, RRB, SSC, and so forth.

Here are some one-word substitutions for group/collection

Battery

A set of weapons or missile launchers operated collectively in one vicinity.

Example -:  

1. We are building a larger battery to restore the power we generate from the river, but … Kelli shrugged.
2. He offered a few battery-powered lighting fixtures to cling at the wagon and Gerald helped him pile hay on the wagon.
3. By using this technique of transmission the battery is usually to the line for the same interval of time, and alternately with contrary poles, so that the effect of electrostatic induction is reduced to a minimal.
4. Incoming currents pass from the line through one coil of the relay, the important thing, and both the battery or battery resistance, according as whether the key’s raised or depressed.
5. In the circuit with this battery become positioned the secondary circuit of an induction coil, the number one circuit of which contained a smartphone transmitter or microphone interrupter.

Constellation

A series of stars is called a constellation.

A constellation is defined as any of the groups of stars in the sky that seem from earth to form a pattern and have been given names. 

 Examples 

1.  This constellation looks like a burger !!
2. “The 48 traditional Western constellations are Greek”
3. The constellation Ursa Major carries the stars of the huge Dipper.
4. A huge constellation of family and friends attended the funeral.
5. Downstairs, to make certain, are the label’s leather-based items, such as an immersive room offering a constellation of Artycapucines.
6. Even in Biba’s shabby apartment, a cheap neon-inexperienced LED light takes on magical residences in one soft scene, its tacky beams skittering throughout enthusiasts’ faces like a moving constellation.

Hamlet

A community of people smaller than a village is called a hamlet. 

Examples 

1. Hamlet is commonly performed as a sorrowful man or woman who cannot make decisions or take action.
2. Inside the saint’s cave at the shore may be seen the rocky shelf on which he made his mattress, however his remains were interred inside the hamlet of Clachan, a few 2 m.
3. The monks lived in separate huts, KaX631a, forming a non secular hamlet on the mountain aspect.
4. Near this hamlet at the coast of the Gulf of Mirabello in east Crete, the American archaeologist Miss Harriet Boyd has excavated an extraordinary part of some other Minoan city.
5. Although the Welsh call of Llanandras is stated to indicate a foundation by means of St Andras ap Rhun ap Brychan within the fifth century the vicinity appears to had been an difficult to understand hamlet in the lordship of Moelynaidd till the 14th century when Bishop David Martyn of St Davids (1290-1328) conferred treasured market privileges upon this his native region, which on dubious authority is said to derive its English call from this priest.

Conclusion

The exercise of ‘One-word substitution’ is, also, something that replaces a phrase with a context however without changing the meaning of the given identical context. One-word  substitution’ is a replacement for long and prolonged sentences or definitions. It falls beneath the class of ‘Vocabulary’ as phrases, sentences, definitions are elements of a speech as well. Here we have specifically discussed the battery, constellation and hamlet.