Located in Quang Ninh, Ha Long Bay is recognized by UNESCO as a World Natural Heritage, famous for thousands of magnificent limestone islands on the blue sea.

With its unique architecture, lantern-lit streets, and rich cuisine, Hoi An is an ideal destination for those who love culture and history.

A highland town with magnificent mountain scenery, terraced fields, and unique culture of ethnic minorities.

The Earth is shaped like an oblate spheroid, which means it bulges at the equator and flattens at the poles. This is due to Earth's rotation, which creates centrifugal force that makes the equatorial region bulge outward.

From space, Earth looks quite round, but in reality, the equatorial radius is about 21 km larger than the polar radius. Specifically, the equatorial radius is 6,378 km, while at the poles it's 6,357 km.

Additionally, Earth's surface is uneven due to mountains, valleys, and oceans. However, on a large scale, the oblate spheroid shape is still the most accurate description.

The most popular language learning app with over 500 million users. The gamification method makes learning fun and maintains motivation.

An app specialized in English pronunciation training with AI, helping to detect and correct pronunciation errors in detail. Suitable for those who want to improve their accent.

Uses the Spaced Repetition System (SRS) to help memorize vocabulary for the long term. Features video clips of native speakers and learning in real-life contexts.