यह बस ट्रेन से सस्ती है, लेकिन ट्रेन उससे तेज़ है।

This bus is cheaper than the train, but the train is faster than it.

Breakdown of यह बस ट्रेन से सस्ती है, लेकिन ट्रेन उससे तेज़ है।

• होना: to be
• यह: this
• बस: bus
• लेकिन: but

Questions & Answers about यह बस ट्रेन से सस्ती है, लेकिन ट्रेन उससे तेज़ है।

Why is it सस्ती and not सस्ता?

Because बस is a feminine singular noun in Hindi, and सस्ता is a changeable adjective that must agree with it.

The adjective changes like this:

• सस्ता = masculine singular
• सस्ती = feminine singular
• सस्ते = masculine plural / some oblique uses

So:

• बस सस्ती है = The bus is cheap.
• ट्रेन सस्ती है = The train is cheap.

In this sentence, सस्ती describes बस, so it must be feminine.

What does से mean here?

Here, से means than in a comparison.

So:

• ट्रेन से सस्ती = cheaper than the train
• उससे तेज़ = faster than that / than it

This is a very common Hindi pattern:

• X Y से बड़ा है = X is bigger than Y
• X Y से अच्छा है = X is better than Y
• X Y से महँगा है = X is more expensive than Y

Even though से can also mean from, with, or by, in this sentence it is specifically the comparison marker.

Why is the comparison expressed as instead of something more like English word order?