The phrase "are occasionally formed" is correct and usable in written English.
It can be used to describe something that happens from time to time or is created intermittently.
Example: "New ideas are occasionally formed during brainstorming sessions, leading to innovative solutions."
Alternatives: "are sometimes created" or "are sporadically developed."
Leagues were occasionally formed, such as the Women's Professional Basketball League (WPBL); begun in 1978, the WPBL lasted only three years.
In the LH, duplexes and thrust sheet stacks were occasionally formed above the mid-crustal ramp, causing growth of the LH from the Middle Miocene to the Early Pliocene (Deeken et al. 2011; Webb et al. 2011).
UEFA Euro 1996 squad UEFA Euro 2004 squad UEFA Euro 2008 squad UEFA Euro 2012 squad 1998 FIFA World Cup squad 2002 FIFA World Cup squad 2006 FIFA World Cup squad 2014 FIFA World Cup squad Before Croatia's independence distinct Croatian football federations and teams were occasionally formed separately from the official Yugoslavian organisations.
Sporadic courtship pairs that were occasionally formed and lasted for only a couple of seconds were not included.
Non-mineralized osteoid tissue was occasionally formed in this type of cultures and hematopoietic cells surrounded it (Fig. 6D).
A stem-loop structure is occasionally formed following every cycle by single primer amplification products, because of the inverted terminal repeats (Fig. 1).
The tapetum might have an important role in kiwifruit because aborted microspores of male-sterile anthers develop an exine and because pollen is occasionally formed in anthers from male-sterile plants by in vitro culture with glucose and CaCl2 (Biasi et al., 2001).
The morphology of hydrothermally-grown YAG crystals is also discussed and several intermediate forms are occasionally observed.
They believe that the seven angels are occasionally reincarnated in human form.
