These groups

[motico]

Please, check if the following passage is grammatically correct. Thanks!

These groups, whose members usually belong to the same ethnic origin, are very hard to be penetrated for gathering intelligence. They are closed and based on personal acquaintanceship and total loyalty to the group. The smaller and the more homogeneous the group is, the more dangerous it might be.

[bhaisahab]

Please, check if the following passage is grammatically correct. Thanks!

These groups, whose members are usually of the same ethnic origin, are very hard to penetrate to gather intelligence. They are closed, based on personal acquaintance and total loyalty. The smaller and more homogeneous the group, the more dangerous it might be.

That's how I would write it.